This invention relates to a bearing for receiving a crankshaft positioned in a crankcase of a marine internal combustion engine. More particularly, the invention pertains to a seal member for sealing the inside of the bearing so as to prevent corrosion of the bearing.
During normal operation of a marine internal combustion engine, the induction air typically contains water which thus enters crank chambers formed within the crankcase, and within which a crankshaft is rotatably disposed. A labyrinth seal is typically used as an air seal between two adjacent crank chambers. Such a seal, however, is not intended to seal the bearings. As a result, the water causes the bearings to rust and thereby reduces their service life.
An object of this invention, therefore, is to provide an improved bearing structure including a seal member for sealing the inside of each bearing to prevent corrosion of the bearings.
Another object of this invention is to provide an improved bearing structure which eliminates the need of labyrinth seals so as to provide a more compact engine in the vertical dimension.